Hydroxymethylated derivatives of resin acids

ABSTRACT

THE PREPARATION OF A NEW SERIES OF POLYOLS DERIVED FROM NAVAL STORES IS DESCRIBED AND THEIR USE IN POLYURETHANES IS DEMONSTRATED. SMALL AOHNTS OF THESE RESIN ACID DERIVATIVES GIVE ADDED STRENGTH TO POLYKTETHANE FILMS PREPARED FROM PROPYLENE GLYCOL POLYETHERS AND COULD VERY WELL BE USEFUL INTERMEDIATES FOT INDUSTRY. INCREASING AMOUNYS OF THESE NEW GLYCOLS BLENDED WITH TRIMETHYLOLPROPANE, 1,4BUTANEDIOL, AND A POLYPROPYLENE GLYCOL AND REACTED WITH TDI GAVE CLEAR STRONG FILMS WITH TENSILE STRENGTHS AROUND 5000 P.S.I. FURTHER ADDITION RESULTED IN HARDER, MORE BRITTLE FILMS. BECAUSE OF THE BRITTLE CHARACTER OF MOST MO FTHE FILMS, KUSE OF THE POLYMERS PROBABLY WOULD BE LIMITED TO COATING APPLICATIONS. ON THE OTHER HAND, CHANGE IN THE FORMULATION IN ONE INSTANCE RESULTED IN FILMS HAVING FAIR LOW TEMPERATURE AND ELASTOMERIC PROPERTIES. THE DIISOCYANATE REQUIREMENTS ARE REDUCED WHEN POLYOLS ARE USED AS A COMPONENT OF THE GLYCOL SYSTEM.

United States Patent Oflice 330L649 Patented Apr. 2, 1974 r r 3801649 HHYDROXYMETHYIZATED DERIVATIVES F CHNHO c 2 HO RESIN ACIDS A John B.Lewis and Glen W. Hedrick, Lake City, Fla., assignors to the UniltedStates of America as represented by the Secretary of griculture NoDrawing. Original application May 12, 1970, Ser. No. \i/

36,672, new Patent No. 3,702,338. Divided and this application Mar. 15,1972, Ser. No. 235,075

Int. Cl. C07c 43/18 10 US. Cl. 260-611 B 1 Claim on, CHa

omo onzono x11 002 onzdrio ,rr ABSTRACT OF THE DISCLOSURE Iva: i=1: 11:0IVb: z=6: zi=3 The preparation of a new series of polyols derived fromnaval stores is described and their use in polyurethanes is 15 3 535 3,?and m do not exceed 5 and the sum of $+w1 is demonstrated. Small amountsof these resin acid derivatives give added strength to polyurethanefilms prepared from propylene glycol polyethers and could very well be Auseful intermediates for industry. Increasing amounts of these newglycols blended with trimethylolpropane, 1,4-

butanediol, and a polypropylene glycol and reacted with TDI gave clearstrong films with tensile strengths around 5000 p.s.i. Further additionresulted in harder, more brittle films. Because of the brittle characterof most of the films,

use of the polymers probably would be limited to coating applications.On the other hand, change in the formula- Cfi 0H20=-- tion in oneinstance resulted in films having fair low temperature and elastomericproperties. The diisocyanate requirements are reduced when the polyolsare used as a component of the glycol system.

Urethane technology is highly developed and many types ofintermediatesglycols, isocyanates, catalysts, solvents, etc.have beendeveloped which have resulted in many end use products. Since there aremany variations, Thls 1S dlvlslon of apphcatlon filed it was decided toconsider only a few of the formulations May 1970 i P for polymerpreparations. More or less standard commer- A lrrvocable royaltyfreehcense m the cial formulations have been published for elastomericinvention herein described, throughout the world for all polyurethanefilms involving the use of polypropylene gly- Purposes of the Umtdstates Government, Wlth the Power col or other polyurethers withtolylene (toluene) diisoto grant Sublicenses for such P p is herebygranted cyanate (TDI). The objective in this invention was to to theGovernment of the United States of America. 40 d t min the eff t theresinyl oiety had on polymer For a number of years a study has beenunderway to properties and to do this, the resinyl moiety was intromakerosin poly-functional and hence, more useful by duced into thepolypropylene glycol polyether chain by addition of hydroxymethyl groupsthrough reaction of reacting II and IIIa with propylene oxide.Polyethers and formaldehyde with resin acids. Another useful variationester-fillers d were blended with P 3- resulted in similar products bythe oxonation of rosin. P pyl glycol 1090, y Q p p and Levopimaric acidin situ in pine oleoresin (pine gum) tanedlol thus obtfiimng glycPlmlxtures having yi g or in the pure state reacts with formaldehydegiving the g ;g;; ag- %g ig i ig mlxed Wlth Diels-Alder adduct (I) whichis readily converted to the P yp cue g a y o Propane' or and IVb) Thisinvention describes the preparation of the acids in dimethyl formamide,DMF as forming the mono glycols (IIIb) and the esters (IVa and IVb) anda progglycol esters. In using this procedure II reacted with more Tessreport on use In some Polyurethane films Whlch than one equivalent ofalkalene oxides as evidenced by may find use in coatings and elastomers.In this invention chemical tests and GLPC. Since the extent ofpolyaddithe glycols are referred to as I'OSlIl derivatives and IOSll'ltion was not much the reaction products were used on polyols. the basisof their hydroxyl equivalent, OHE, and in the text are consideredmonoglycol additions. Polyester formation from II was possible and mayhave occurred to some extent. This was not considered detrimental sincethe end product would be a diol and useful in subsequent reactions. Thehydroxymethyl group at the C-12 posi- (IJHKOH (fHIOH tion did not reactunless catalyzed by catalysts other k 12 than DMF. With KOH as acatalyst in dioxane, the 12- -0 n hydroxymethyl group for some reasonwas more sluggish l i 9 in than the glygol esger group at fthe Citposition and an ,1 average 0 a out t ree mo es 0 propy ene oxide was all\I/ f that could be added to the methylol group (Table I). It EL I isbelieved that the hydroxymethyl at the C-4 and C-l2 4 position of IIIareacted with propylene oxide at about equal rates becausetetrahydroabietanol and the 12-hy- C0211 COZH CHQOH droxymethyl group ofNa seemed to react at about the I 11 111 same rate, neither wasparticularly sluggish.

TABLE I-COMPARATIVE REACTIVITY OF HYDROXYL GROUPS IN GLYCOL (Iva) Ratioof Mole ratio of propylene oxide 1 Minimum to achieve complete reactionwith We.

Both II and III are sparingly soluble in propylene oxide and havemelting points above the reaction temperatures for alkalene oxides.Because of these properties, a solvent (dioxane) was used to avoiduncontrollable and explosive conditions.

Chitwood and Freure ['I. Am. Chem. Soc., 69, 680 (1946)] have shown thatthe base-catalyzed alcoholysis of propylene oxide resulted in a primaryalkoxy derivative and a secondary alcohol. More recently, St. Pierre andPrice [1. Am. Chem. Soc., 73, 3432 (1956)] and Dege et al. [1. Am. Chem.Soc., 81, 3374 (1959)] agreed with this hypothesis and cited a number ofother supporting references. This configuration has been used in theformulae in this invention.

Price observed appreciable end group unsaturation from the catalyzedpolymerization of propylene oxide and Dege and his collaboratorsconfirmed this and developed methods for determining the extent of theunsaturation based on chemical tests and infrared spectroscopy. If therewas end group unsaturation in the glycols reported herein, it was minorsince no unsaturation was observed using the test methods referred toabove.

some polymer formulations with TDI, trimethylolpropane, TMP,1,4-butanediol, and polypropylene glycol, PPG 1000 and their propertiesare given in Table II. Item I is a formulation reported by the Du PontCompany (PB-2 and PB-4) and is included for comparison with the otherpolymers from PPG.

The significant point is the amount of TDI and TMP which presumably wasrequired to produce an acceptable film. The formulation in item 2 wasselected as being suitable for modification by incorporation of rosinpolyols and has been used as a control. The other item, 3, was includedin Table II to show the eifect minor variations in formulation,especially an increase in TDI, had on polymer properties. Tables III,IV, and V give the formulations and test results when the rosin polyols111b, IVa, and IVb were substituted in varying amounts for some of the1,4-butanediol and PPG 1000 used in the control. As the glycols wereadded, both the butanediol and PPG 1000 had to be decreased to avoid achange in the average hydroxyl value of the glycol mixture ofapproximately 213.

The effect of the addition of the rosin polyols in increasing amountswas to increase the tensile strength, stiffness, abrasion, and hardness;results which are ordinarily obtained by raising the NCOzOH ratio.Maximum tensile strength was obtained with a resinyl moietyconcentration of about 10% for Na and IVb and 15% for IlIb. The glycol(IVb) seemed to produce the hardest films and IIIb gave the softestfilms per unit of glycol added.

Specific comments on the tables follows. In Table III there was a rathermarked decrease in butanediol in the formulations which was necessarybecause of the low hydroxyl equivalent value of Na. In general, theeffect of decreasing the butanediol in this manner would result insofter films rather than harder films as indicated.

TABLE II.POLYURETHANE FILMS FROM POLYPROPYLENE GLYCOL 1000 Ave. Elonga-PPG OHE Ten tion at TMP Bu(OH)a 1000 TDI NCO OH glycol strength, Modulusbreak, equiv. equiv. equiv. equiv. ratio mix p.s. 100% percent Comments6 b 0. 2 0. 2 1. 6 1:6:1 135. 9 7, 500 40 Hard brittle film. 0. 39 0.0.5 1. 41 1. 05:1 214 1, 200 567 288 Soft, pliable, clear elastomer. 0.45 0. 45 0. 45 1. 1. 19:1 197 2, 847 4. 026 188 Clear, flexible,slightly stifi film.

h Du Pont (PB-2 and P134). 5 1,3-butanediol. Elastic modulus.

TABLE IIL-POLYURETHANE FILMS FROM PROPYLENE GLYCgL12-HYDROXYMETHYLDIHYDROABI- ETATE (IVa). OHE 20 Cone. Ave. Abra- Rosinof (II) PPG OHE Tensile Modulus Elonga- Stifision derlv. percent Bu(OH);; 1000 glycol strength, on, ness, Hard- 10- equiv. in film equiv.equiv. mix p.s.i. Elastic 100% percent Tf, ness percent a 0. 12 5. 0 0.38 0. 45 212 1, 678 865 277 e 0. 25 10. 0 0. 0. 41 212 5, 317 13,000 1,290 251 16. 5 41 0. 8 l 0. 35 14. 4 0. 23 0. 37 213 5,050 49, 700 1, 985220 3. 0 63 1. 22 l 0. 49 19. 9 0. 15 0. 32 212 4, 716 133, 000 170 7. 579 3.02 0. 50 19. b 0. 33 432 3, 794 1,524 240 -21 79 1.13

I TMP 0.39 equiv., TDI 0.14 equiv., NCO :OH ratio 1.05:1. PPG 2000instead of PPG 1000; TMP 0.33 equiv., TDI 0.141 equiv., NOOzOH ratio1.22:1. I Too hard.

TABLE IV.POLYURETHANE FILMS FROM PROPYLENE GLYCOL ESTER-ETHER (IVb)Cone. Ave. Rosin oi(1l) PPG OHE Tensile Modulus Elonga- St1fi- Abrasionderiv. percent Bu(OH) 1000 glycol strength, t10n, ness, Hard- 1 equiv.in film equiv. equiv. mix p.s.i. Elastic percent Trf C ness percent a 0.5. 0 0. 44 0. 39 212 1, 264 215 293 a 0. 260 10. 5 0. 42 0. 270 213 5,166 8, 780 280 13 Soft 0. 31 b 0. 367 15. 0 0. 44 0. 213 4, 750 100, 000253 2. 5 73 0.39 l 0. 490 20. 8 0. 39 0.007 213 5, 270 160, 000 194 6. 086 1. 76 a 0. 614 25. 1 0. 25 241 3, 401 247, 900 44 45. 5 95 3. 28 I0.734 28. 2 307 2, 883 195, 664 76 29. 0 81 9. 39

B OHE 438.4.

b OHE 480; TMP 0.39 equiv. for Items 1, 2, 3, 4; 0.34 equiv. for 5; and0.37 for 6. N00 to OH ratio 1.05:1 for Items 1, 2, 3, 4, 5; and 1:1ratio for 6; TDI 0.141 equiv. for Items 1, 2, 3, 4; 0.120 for 5; and0.110 [or 6.

6 Too hard.

TABLE V.--POLYURETHANE FILMS FROM POLYPROPYLENE GLYCOL ETHER (IIIb)Cone. Ave. Modulus Abra- Rosin 01 (V) PPG OHE Tensile Elon- Stiflsronderiv. percent Bu(OH); 1000 glycol strength, Elastic gation, ness, Hard-10- equiv. in film equiv. equiv. mix p.s.i. 100% 100% percent Tr, C.ness percent 1 I 0. 254 10. 0.444 0. 254 213 2, 561 2, 537 436 275 --14.48 0. 28 2,- I 0. 381 15. 0 0. 435 0. 134 213 4, 911 9. 097 694 301 -1.0 0. 96 3.- I 0. 520 20. 5 0.430 213 5, 094 47, 500 1, 747 244 5. 0 593. 91 4.. b 0.636 25. 0 0.235 241 3, 862 167, 964 Hard Hard 0. 5 79 5.09 5.- e 0. 558 23. 9 0. 233 274 2, 866 2, 303 347 --50. 0 1. 04 6 2.000 2.000 270 4, 200 640 800 76 l OHE 515. I OHE OHE TMP 0.394101.-Items 1 2, 3; 0.36 for 4; and 0.34 for 5; TDI 1.41 equiv. for Items 1,2, 3; 1.29 equiv. for 4; and 1.17 equiv.

for 5; NCO to OH ratio 1.05:1.

d Schollenberger (1969), modulus at 300%; Shore A hardness; MDI 4.0equiv.

Too soft.

Item 5, Table III is similar to item 4 in composition. resinate. Asecond crop of less pure material was obtained The only difference is inthe use of PPG 2000 instead of PPG 1000 and it illustrates thepossibilities of variations in formulae. Films in this instance withoutthe rosin polyol with 1.05 :1 NCO to OH ratio were soft and tacky.

In Table IV the results of items 1 through 4 are about as expected. Itshould be noted that the glycol for item 3 had a higher OHE value (480)than that used for others of the series and may have had a minor but notvery significant effect on the properties since the results seem tocorrelate well with those of items 2 and 4. Items 5 and 6 were added toshow the eflect, of larger amounts of the rosin derivative. The filmsmight be useful for coatings but were too brittle and too hard forelastomers.

The first four items for Table V require no comment since the discussionconcerning Tables III and 1V is applicable'here. The formulation of item5 was included principally to show that films can be made withreasonably good elastomeric and low temperature properties, T, -50 C.

Item 6, taken from current literature, is added for comparison purposes[C. S. Schollenberger, Polyurethane Technology, 10, 197 (1969)].

Unless otherwise specified, gas liquid partition chromatographic (GLPC)analyses were made on an F&M 700 chromatograph using a 6 ft. -98silicone Hewlett-Packard Vs inch column at 235 C.

EXAMPLE 1 12-hydroxymethyldihydroabietic acid (II)12-hydroxymethyldihydroabietic acid, a mixture of dihydroderivatives,was prepared by hydrogenating 12-hydroxymethyladietic acid. The adduct(I) (525 grams; 1,58 moles) was dissolved in a mixture of 1050 ml.ethanol or methanol and 150' ml. of 3 N hydrochloric acid. This wasblanketed with nitrogen, stirred until solution was complete, andallowed to stand overnight. The solvent was partially removed in vacuo.The mass was poured into a water-ice mixture while stirring. Seedingfacilitated crystallization. The acid was washed acid-free with water ona Biichner filter, dried at about 50 C. (water aspirator vacuum), andrecrystallized from 75 aqueous methanol. An alternate method consistedof dissolving the precipitated acid in ether or benzene, then washing toremove mineral acid. The solvent was removed and the productcrystallized from 75% aqueous ethanol. Yield: 480 g.; 91.5%. Calculatedfor C ,H O Neutral equivalent: 334.27. Found: 335; M.P. 162-164 C.[reported 166.5- 168 C. by Parkin and Hedrick, J. Org. Chem., 30, 2356(1965)].

A more convenient isomerization was achieved by dissolving 15 lbs. ofadduct (I) in 35 lbs. methanol, adding 7.5 lbs. of a strong acid ionexchange resin of the sulfonic acid type, warming to 40 C., andagitating until the adduct was-all .in solution. Isomerization was rapidand complete in about one-half hour. The reaction was monitored by useof ultraviolet spectroscopy. Filtering to remove the resin, adding waterto give 75% methanol, and cooling gave 13.6 lbs.; 91% of H. The GLPCchromatogram' of the methyl ester 'hada minor peak for a methyl bydiluting the filtrate to 60% methanol.

The abietic acid derivative (400 g.; 1.2 moles) in 400 ml. methanolhydrogenated rapidly at room temperature using 6.6 g., 5%palladium-on-carbon catalyst and good agitation; no conjugated diene wasleft after about 1.5 hours with hydrogen at 10 p.s.i. The catalyst wasremoved for reuse by filtration of the solution (hot). Crude 12-hydroxymethyldihydroabietic acid (II) crystallized as the solutioncooled; 350 g.; M.P. pure 194-195 C. (methanol). GLPC of the unpurifiedmixture had a major peak (the above) and two minor peaks appearing asshoulders on the major peak. Calcd. for C H O Neut. equiv., 334.27;hydroxy equivalent (OHE) methyl ester, 348.29. Found: Neut. equiv., 336;OHE methyl ester, 350.01.

EXAMPLE 2 Monopropylene glycol ester of l2-hydroxymethyldihydroabieticacid (IVa) The hydroxy acid (H) (500 g.; 1.49 moles) was dissolved indry dimethylformamide (500 ml.) and heated to C. in a flask equippedwith an agitator and condenser for use with Dry Ice as a coolant.Propylene oxide (100 g.; 1.7 moles) was added dropwise to maintain agentle reflux. After about 3 hours the acid content was nihil. The bulkof the DMF was removed by distilling in vacuo. The residue was pouredinto water, dissolved in ether or benzene, and washed, first with dilutemineral acid, and then with dilute soda ash and water. The solvent wasremoved in vacuo, 100 C. at less than 0.5 mm. Hg pressure, 580 g. Calcd.for C H O OHF, 196.16; saponification equivalent (sap. equiv.), 392.32.Found: OHE, 205; sap. equiv. 408. Neut. equiv. of the acid from asaponified sample was 337. GLPC of Na showed a major peak and at leasttwo minor broad peaks indicative of the esters of dipropylene andtripropylene glycols.

EXAMPLE 3 Mixed polypropylene glycol ether-ester (IVb).

Hydroxy acid (H) (200 g.; 0.6 mole) was dissolved in a dry hydrogenperoxide and acid-free dioxane and charged to a pressure reactor with2.1 g. potassium hydroxide pellets and propylene oxide (418 g.; 7.2moles). The reactor (a rocking type) was heated to to C. for 4 hours.The pressure variation was from 188 to 42 p.s.i. at the end of thereaction. The product was removed from the bomb and most of the solventwas distilled (100 C. at 1 mm. Hg). The residue was dissolved in ether,washed with dilute hydrochloric acid, then water until chloride-free anddried over MgSO Removal of solvent (100 C. at 1 mm. Hg) gave 507 g.clear, light amber, mobile liquid, acid number 0.3; OHE 438.4; sap.equiv. 876.09. The ether-ester was also prepared from the monoglycolester (IVa) by dissolving (Na) in dioxane; adding catalyst, propyleneoxide; and proceeding as above.

To determine the reactivity of the two hydroxyl groups on the initialglycol, IVa was reacted neat using potassium hydroxide catalyst withvarying amounts of propylene oxide at 140-150 C. Accordingly, IVa wasreacted with 7 4:1, 8:1, 12:1, 16:1, and 20:1 molar equivalents of thealkalene oxide. Determination of sap. equiv., OHE and neut. equiv. ofthe saponified acid resulted in the data in Table I.

EXAMPLE 4 Polypropylene glycol diether ('IIIb)12-hydroxymethyltetrahydroabietanol (Illa) [M.P. l82.5-183.5 C. frommethanol toluene mixture (31 to 69 ratio on weight basis)] (146 g.; 0.45mole) was dissolved in dioxane (see above) (146 g.) and reacted withpropylene oxide (418 g.; 7.2 moles) using as catalyst, potassiumhydroxide (2 g.) in a rocking type pressure reactor. The reaction wascomplete in 3 hours at 150- 160 C. as evidenced by pressure drop. Theproduct was isolated in the same manner as used for lVb, 535 g. ambercolored, mobile, viscous liquid; OHE 515.

In another run using 4 mole equivalents propylene oxide, the hydroxylequivalent was 264. The mixture of acetates on GLPC using a A" x 3',/2%, SE. 30 column gave no peak for the diacetate of the starting glycol(Il'Ia).

To obtain insight as to the reactivity of the presumably stericallyhindered -4 hydroxymethyl group of IIIa, tet-rahydroabietanol (53 g.;.18 mole) was reacted in a closed container at 140-150 C. with propyleneoxide (42 g.; 72 moles) in 53 g. dioxane containing .18 g. potassiumhydroxide. After 4 or 5 hours the pressure dropped from 100 to 22 lbs.The product (82 g.) (100%) contained (by GLPC) less than 5%tetrahydroabiethanol OHE 451; 274 moles propylene oxide added. NeitherIIIb or IVb had any discernable end group unsaturation using the methodsof Dege et a1. [1. Am. Chem. Soc., 81, 3374 (1959)],

EXAMPLE 5 Polymer film formation The glycols 1,4-butanediol,trimethylolpropane, the rosin derivative, and polypropylene glycol weremixed and degassed at 60 C., 0.2 mm. pressure. The glycol mixture wascooled to 30 C., the isocyanate added, and the mixture warmed to 85 C.(slightly exothermic). The flask was evacuated to exclude air and at theend (40 to minutes) degassed at 0.2 mm. pressure. The clear, almostcolorless, mobile liquid was poured hot into molds maintained at -110 C.which consisted of a '6" x 6" (inside) aluminum metal frame clamped to aA-inch thick aluminum sheet covered with thin aluminum foil. Thereaction was poured onto the foil in an amount (about 42 g.) so thatapproximately A -inch thick films resulted. Two to three hours at100-110 C. were required for curing. The next day the films withaluminum foil backing were immersed into a dilute hydrochloric acidsolution to dissolve the foil that could not be removed readily by hand.

Formulations and polymer properties are tabulated in Tables 11 throughV.

We claim:

1. A compound represented by the formula om crno cmhno x,H

wherein x and x do not exceed 5 and the sum of x+x is at least 1.

References Cited UNITED STATES PATENTS 2,724,700 11/1955 Barker 260-611B X FOREIGN PATENTS 908,010 1'0/ 1962 Great Britain 260-611 B BERNARDHELFIN, Primary Examiner US. Cl. X.R.

2606ll F, 77.5 AP

